1. Field of the Invention
The present invention relates to the field of liquid crystal displaying techniques, and in particular to a backlight module and display device thereof.
2. The Related Arts
In liquid crystal display devices (LCD), backlight module is a key component of a liquid crystal display device. The main function of the backlight module is to provide a light source with sufficient luminance and uniform distribution so that the liquid crystal panel can display images normally.
In general, the LED backlight source of the backlight module is categorized as direct-lit type or edge-lit type. FIG. 1 is a schematic view showing the edge-lit LED backlight source of the backlight module of a known LCD, which comprises an LED light bar 10 and the active area (AA) of the LCD. A is the length from LED light to AA, and P is the distance between two adjacent LEDs. The ratio A/P is usually greater than 0.5. However, in the backlight module with edge-lit LED backlight, the A becomes smaller as the frame rim of the backlight module narrows. When A/P ration is less than 0.5, a hotspot phenomenon will appear, which severely affect the optical characteristics of the backlight module and the display quality of the display device.